Altered Functional Connectivity of the Insula and Nucleus Accumbens in Internet Gaming Disorder: A Resting State fMRI Study

Aims: A possible addiction mechanism has been represented by altered functional connectivity (FC) in the resting state. The aim of this study was to evaluate the FCs of the insula and nucleus accumbens among subjects with Internet gaming disorder (IGD). Methods: We recruited 30 males with IGD and 30 controls and evaluated their FC using functional magnetic imaging scanning under resting, a state with relaxation, closed eyes, with inducement to think of nothing systematically, become motionless, and instructed not to fall asleep. Results: Subjects with IGD had a lower FC with the left insula over the left dorsolateral prefrontal cortex (DLPFC) and orbital frontal lobe and a higher FC with the insula with the contralateral insula than controls. The inter-hemispheric insula connectivity positively correlated with impulsivity. Further, they had lower FC with the left nucleus accumbens over the left DLPFC and with the right nucleus accumbens over the left DLPFC, and insula and a higher FC with that over the right precuneus. Conclusion: The elevated inter-hemispheric insula FC is found to be associated with impulsivity and might explain why it is involved in IGD. The attenuated frontostriatal suggests that the emotion-driven gaming urge through nucleus accumbens could not be well regulated by the frontal lobe of subjects with IGD.